The Ubiquitin Ligase PUB22 Targets a Subunit of the Exocyst Complex Required for PAMP-Triggered Responses in Arabidopsis [C][W]

@article{Stegmann2012TheUL,
  title={The Ubiquitin Ligase PUB22 Targets a Subunit of the Exocyst Complex Required for PAMP-Triggered Responses in Arabidopsis [C][W]},
  author={Martin Stegmann and Ryan G. Anderson and Kazuya Ichimura and Tamara Pe{\vc}enkov{\'a} and Patrick Reuter and Viktor Ž{\'a}rsk{\'y} and John M. McDowell and Ken Shirasu and Marco Trujillo},
  journal={Plant Cell},
  year={2012},
  volume={24},
  pages={4703 - 4716}
}
Exo70B2, a subunit of the exocyst complex, which is involved in exocytosis, is targeted for degradation by the ubiquitin ligase PUB22 upon activation of the immune system. This work also reveals that Exo70B2 is required for the activation of PAMP-triggered responses. Plant pathogens are perceived by pattern recognition receptors, which are activated upon binding to pathogen-associated molecular patterns (PAMPs). Ubiquitination and vesicle trafficking have been linked to the regulation of immune… 

Figures from this paper

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TLDR
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TLDR
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TLDR
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A Truncated NLR Protein, TIR-NBS2, Is Required for Activated Defense Responses in the exo70B1 Mutant
TLDR
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The Pseudomonas Syringae Effector AvrPtoB Associates With and Ubiquitinates Arabidopsis Exocyst Subunit EXO70B1
TLDR
It is shown that EXO70B1 is required for pathogen-associated molecular pattern-triggered immune responses in Arabidopsis thaliana and AvrPtoB enhances Pto DC3000 virulence by overcoming EXO 70B1-mediated resistance.
Proteasome-associated HECT-type ubiquitin ligase activity is required for plant immunity
TLDR
It is shown that specific members of the HECT domain-containing family of ubiquitin protein ligases (UPL) play important roles in proteasomal substrate processing during plant immunity, and it is demonstrated that UPL3 enabled proteasomes to form polyubiquitin chains, thereby regulating total cellular polyubiques levels.
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